Mechanism for filling dispensing guns



July 21, 1953 H. c. PAULsEN 2,646,199

MEcHANIsM FOR FILLING. DISPENSING GUNS Filed March 17, 1950 2 Sheets-Sheet 1 zagg.

lve/zior @Pau/.sen

July 21, 1953 H. c. PAULsEN 2,646,199

MECHANISM FOR FILLING DISPENSING GUNS Filed March 17, 1950 2 Sheets-Sheet 2 I @I if@ Patented .uy 21,` 19513 Hans C. Paulsen,l Medford, Mass.,` assignor to United Shoe Machinery Corporation, vFlemington,'N. J .,'acorporation of New Jersey Application March 17, 1950, Serial No.-150,291 Y l :This"inventionrelates, to extruding mechanisms for plastic materials and is herein illustratedr as embodied in` mechanism forguse in v iilling plunger-.operateddispersing vguns which `are separable from the extruding mechanism and capable of use for theapplication of plastic material to a piece of Work, y'

Numerous plastic materials are yappli-cable to I the manufacture of shoes and can be employed,

when softened, as adhesives for sticking together shoe parts. vIf such plasticmaterials are contained'in a receptacle which'` iskep't' heated for a considerable period, it 'has been found that there is considerable diiiicultyin preventing .such an overheating of the materials as may readily cause a change in the characteristics thereof and 'which frequently entails a great deal of difculty in keeping the receptacle clean after the material has been softened and rehardened ra'numberof times. One way of avoiding some of these diiii' culties is to utilize a plastic `material which is in granular form and to deliver. it, a little at a time,

to an extruding machine where this material .isV

animprovedextruding mechanism arranged tov facilitate the deliveryof the granularfmaterial to the extruder passage.

Such extruding mechanisms' comprise a feed screw operating inV a passage between the inlet and the outlet openings. In machines of this type there is a tendency for the feed screw, ata point adjacent to the inlet opening, to' push the material vtoward one side where it may accumulate and become suiciently softened to 4bridge' the opening'. To avoid thatdifhcu'lty the illusjtrated machine is provided with an auxiliary feed screw shown as meshing with the principal feed screw at the inlet opening and turning inthe opposite direction, at a level slightly 'higher'than thelevel of the main feed'screw. y

'It is frequently desired, especially in themanufacture of shoes, to `treat successive pieces of work each requiringjonly a small quantity of the materialand in some cases itis found convenient 'to employ a portable dispensing gun by which the material may be applied to the WorkA under thel control of the operator. This very element of portability, however, precludes the 6 Claims. Cl. 226;7@

gun from having a considerable capacity andjit must be simply constructed so that the dispens .ing shall beat thewill of the operator. One

very simple type of such a gun includes a plunger the shaft of whichis accessible to the operator andis provided with'a knob operated by pressure of the operators thumb to dispense the mate.

rial.

With this tion resides `in the provision of `an automatic mechanism for shutting off .the power driving the feed screw .of .theextru'din'g mechanism when the gun has been lledto a predetermined degree.Y

member for the purpose previously described.

These and other features of the: invention will ,A

best be understood'from ,a consideration of the following specification taken in Vconnection with thejaccompanying iravvings in which Fig. l is asideelevationof the extruding inechv anism vn icludirig the electrically lcontrolled drive I therefor;

Fig; 2 jis a side elevation of a dispensing ygun having amanuallyoperated plunger; Y

Fig. 3 is avertical section on the line III-IIL of 1 showing the feed hoppei'land a chute for delivering the granularfmateria'l to theinlet opening ofthe extruding mechanism;

Fig. 4 is a section on y,thefline IV-IV of Fig. 1 looking ata portion of the drive mechanism;

Fig. 5 is an end elevation, on a v'larger scale, of the extruding mechanism, the associated 4switch operated member and a dispensing gun vin the position which it' occupies when being moved into place to receive acharge .of material;

Fig... 6 1'S a, YSunil-a1 View .but with the turned Vto the positionoccupied during the filling of the gun;

Fig. 7 is asubstantially horizontal section on the lineiVIIf-'VII of Fig. '6 and showing the drive-v controlling .switch gFig. 8 is a vertical axial section through the end Y of the' extruding mechanism `with the gun in receiving position; and

Fig. 9 is asection through'the vend "ofthe extruding mechanism lookingdoWn upon the operating knob of the gun.

The extruding mechanism comprises an elon-` r' gated block i0 mounted upon a-supportingframe -l2 and containingaI -feed screw i4' rotated in an in mind, another object of the inven-Q elongated passage I6 in the block to carry granular material received at an inlet opening and delivered to an outlet opening (Fig. 8) shown as formed in a screw fitting 22 which closes the end of the passage |6. The block is preferably surrounded with heat insulating material 24 and is providedwith electrical heating units 26 and 28 arranged along side the feed screw I4 so that granular material 'deposited in the inlet opening is heated progressively as it moves along the passage |6. By the time it reaches the outlet opening 20 it has been melted so that it may be readily extruded through that opening.

It will be noted that the inlet opening I8 (Fig. 3) is of a hopper shape. Associated with the opening is a chute 30 having a shielded end 32 positioned directly above the hopper-like opening I8. This chute, to keep it as cool as possible, is mounted upon a bracket post 34 extending upward from the frame 2 and used also to support a hopper 36 in which a supply of the granular material-may be placed. At the bottom of this hopper there is a driven feed screw 38 the end of which lies adjacent to an opening 40. The size of this opening may be controlled by means ofV a slide cover 42 connected to a thumbscrew 44 for moving the slide horizontally. Duplication of the position of this slide is facilitated by a pointer thereon cooperating with a scale v46.

It will be seen from an inspection of Fig. 3 that there is a tendency for the principal feed screw I4, rotated in the direction of the arrow, to push the material toward one side of the inlet opening .I8 and if this material accumulates and stops there long enough it will become softened and tend to bridge the opening. This diiiiculty'v isl overcome, however, by the employment of an auxiliary feed screw which extends along the main feed screw for a distance' approximating the length of the feed opening and the block at the forward side of the feed opening is undercut as indicated at 52 in'Fig. 8. The main and thel auxiliary feed screws are rotated in opposite directions and their `ribs intermesh so that granular Ymaterial deposited from the chute 30 is continually pushed into the elongated passage I8 and carried forward therein by the principal feed screw I4. n

For drivingthe various feed screws an electric motor Vmay be connected through reduction gearing 62, a sprocket 64 and a chain 66 to another sprocket 68 joined to the outer half I0 of a friction clutch. This outerhalf of the clutch is loose upon the shaft '|2 of the feed screw I4 and when moved to the right in Fig. 1 grips the inner clutch cone '|4 which is attachedY to that shaft. Another and smallersprocket 16 (Fig. 4)

'|0of'the clutch into engagement with the otherY half '|4. The lower end of this lever 82,which`i`s swung to the left by a spring V88, is adapted to be operated by a solenoid 90. vThis has a core 92 connected to the lever B2 through a spring 9 4 to soften the action. The energization of this solenoid is effected by power transmitted through` a microswitch 96 (Figs. 1 and 7) which is closed whenever a spring button 98 therein is released. Mounted adjacent to this button is a swinging lever |00 which turns on a screw |02 to a limited extent, there being a spring |04 to create friction between the lever and a base plate |06 on which it is mounted. This plate is carried by a bracket |08 on the frame I2 adjacent to another bracket |I0 which supports the solenoid 90. Movement is imparted to the switch actuating lever |00 by stop screws I I2 adjustably positioned A upon a slide I I4, the latter being guided upon the base plate |06 by a screw ||6 passing through a slot in the slide. On this slide is a rod I |8 having Vahead |20 for a purpose to be later explained.

When the extruding device is to be used for lling a portable dispensing gun |30, the passage I6 is provided with a lining sleeve |22 shown as integral with an end plate |24 which is held on the block I0 by means of screws |26 (Fig. 6). At the inner end of the lining sleeve |22 there is threaded the screw fitting 22 which is provided with a conical recess coacting with the sleeve |22 to form a socketfor the reception of the barrel |28 of the dispensing gun |30. The outer end of the barrel has an enlarged head |29. Within the barrel of the gun is a plunger |32 having a stem |34 which slides in a bushing |36 (Fig. 8) threaded in the head |29. Mounted on the outer end of theV stem is a knob |38 having a lug |40 for a purpose which will later appear.

It will be seen from Fig. 8 that the dispensing opening at the end of the tapered portion of the barrelV |28 of the gun is alined with and close to the outlet opening 20 in the fitting 22. Since the plastic material is forced into the gun with considerable pressure, it is necessary to hold the latter in its socket and to this end the outer end of the barrel of the gunrhas a partial circumferentially extending ange |42 projecting from the head |29. Mounted on the end plate |24 is an outwardly extending canopy I 44 having an upturned end flange |46 which is slidable upon the stems of screw studs |48 and which is forcibly held against the end plate by springs |59 surounding those stems. This canopy has a slot |52 (Fig. 9) adapted to coact with the flange |42 on the gun to lock the latter in place when the gun is pushedv into its socket as far as it wil-l go and then given a partial rotation from the position of Fig. 5 to the position of Fig. 6. Handling of the gun is made easier by providing the head |29 with an integral laterally extending prong |54 on which there is mounted a handle |56. This handle is provided with an abutment |58 which cooperates with the right edge of the canopy |44 to guide the gun barrel into its socket into the position of Fig. 5. At that time the edge of the locking ange |42 slides along the left edge of the canopy. It should be noted that rotation of the knob |38 with respect to the barrel of the gun |30 is prevented by'a tongueV |60 (Fig. 2) which is integral with the gun and which slides in a groove |62 in the periphery of .the knob.

It being desired to stop the drive for the extrusion device when the barrel of the gun is filled with plastic material, provision has been made for connecting the knob |38, which is attached to the plunger |32, to the head |20 of the switch operating mechanism. Consequently the head 29 is provided with a projection I 64 which, when the gun handle has been turned to the position of Fig. 6 to lock the gun to the extruding apparatus, is `in alinement with the lug |40 on the knob. The head is also provided with a latch si 'I (Fig. y'7.) which-normally'projects from the, face ofxthe. head in the manner shown in that' `It is held Ain projecting positionwby a iigure.

asia-reef:

spring surrounding the stem of the llatch'and' limited as' toinward movement byretaining nuts on the end ofthe latch. It willffbe noted that the inner end of the latch is notched to provide a hat surface for'lengagement by the inner face of thelockingpflange '|42 when the gunfis positioned as in-Figlf and is being pu'shedhome and has an inner lend surface which is inclined to the axis of the guns so that the latch maybe pushed aside by the flange |42 onthe yiilled gun which flange is, at that time, back of said` latch.

It will be noted that the block 0 and the sleeve |22 are provided with registering overowdischarge openings |12, Vclosed bythe gun while'it is being lled but opened when the gun is displaced axially, as later described.

In the operation of the device, the gun will be: inserted in its socket under the guidance ofthe abutment |58 sliding along the yside of the canopy until theguncan be turned clockwise to enter the lange |42 in the slot |52. rDuring its inward movement, the flange |42 will engage the notch of the latch |110 thereby pushing inthe slide H4 to operate the switch and start 'the drive of the extruding mechanism. The extruded plastic material issuing through the outlet will enter the opening in the end of the gun barrel and as the barrel is filled will push back the plunger and its stem |34 thereby moving the knob |38 to the left in Fig. 7. Asthe gun becomes lled the lug |43 on the knob will engage the projection |64 from the switch operating head IZD, moving the slide H4 to the left and swinging the lever |99 to allow the switch Ybutton Y lOl able to allow displacement .of the container under pressure of the extruded material therebyftoi open the overflow passage. l'

2. In combinatiom av plunger-operated'dispensing gun, an extruding mechanism for filling said gun,xsaid plunger having a knob outside the gumsaid extruding mechanism having means to receiveand. support the gun whileit is' beingvk filled, coactingV members yon the gun' and thev mechanism for holding the two in engagementv during-the illin'g and arranged to be brought into operative relation by partial rotationlof- 'the' gun-'in its support, said Aextruding mechanism having a feed member adapted to be vconnected to electric drive,l a switch for controllingJ said electric drive, a ymovable switch-operating 98 to'protrude, thus shutting on the flow oi" current to the solenoid S0 and permitting the spring 88 to swing the clutch lever 82 and discontinue` If thereis any malfunction of the the drive. i parts, there is no danger of breakage because the advancing plastic material will simply push the gun barrel back in its socket, compressing the springs |553 surrounding the studs which support the canopy |44. This will allow the excess extruded material to pass between the fitting 22 and the tapered end of the gun barrel and to drain orf through the overow discharge opening i12. After the drive has been disconnected the gun may be removed from its socket by turning the handle to the position shown in Fig.. 5,. This will carry thelug |40 out of alinement .with the projection |4 on the switch operating' member but it vwill bring the ange |42 behind the inner end of the latch |10. of this end of the latch will permit `it to snap o back out of the way as vit is contacted by the iange |42. f i

Having `thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1. In an extruding machine for plastic mate- However, the inclination y rials, an elongated block having a feed passage extending lengthwise thereof and provided with a socket at its outlet end for receiving a container to be lled, said socket having an overflow discharge opening adjacent to andgpositioned to be closed by the inserted container,v

means for holding a container injsaid socket,

means for heating said block, and a feed screw in the passage driven to carry granular material which is progressively melted as it proceeds along the rpassage and is extruded into the container, said container holding means being yieldmember suppcrted on the extruding mechanism adjacent to the gun-receiving v portion thereof,` cooperating guidemembers on the gun and the eXtrud-ing mechanism to lead the gun'into op-` erativev relation to the extruding mechanism; coacting lugs 4on the'switch-operatingmember andl on-the knob adapted `to pass one another asthe gun is moved into position under the guidance vof said coacting members, and means for use in imparting a partial rotation tothe supported ,gun to bring said lugs into alinement so that externally positioned knob, a latch on said switcho operating member, means on the gun forpushing the latch to carry .the switch-operating member to drive position as the gun is inserted in` its supporting means, and a lug on the knob for engagement with said switch-operating member to move it in the other direction as the plunger is pushed back by the plastic during the filling of the gun, to stop the drive.

4. In an extruding machine for plastic materials, an elongated Vheated blockprovided withY a longitudinal passage, one end of the passage being recessed in a shape =to receive a portion of a container to be filled, means to hold said containerV to the block, the other end of the passage forming an inletV hopper opening in'the'block above the passageto receive aY sup-ply of plastic mate- `rial in granular form, a feed screw in the passage for carrying the material into the .afvoresaidcon- ,tainer, that edge surface of the hopper-like inlet opening which is above the feed screw where it Venters the main passage being sloped inwardly and thus undercut, a reverscly threaded auxiliary feed screw in thehopper portion on thelside to- 'ward which .the top of the feed screw rotates, and

means ifor driving said screws in opposite directions.

5.r The combination or a portable, plunger-containing gun to be lled and an extruding machine .for forcing plastic material into the gun, in which the extruding machine comprises a `hollow casing containing a driven extruding member, the hollow casing being provided with an outlet 4against which the gun is seated with its dispensing opening in register with said outlet to receive extruded material, with a resultant movement of the plunger as the gun is lled, a switchoperating member movably mounted on said extruding machine, and coacting means upon the gun parts and the casing of the extruding machine for holding the gun seated against the outlet and for connecting the plunger of the gun to the switch-operating member to cause the extruding member to be stopped when the gun has been lled.

6. An arrangement, for lling a gun provided Witha dispensing opening and containing a movable plunger, which consists of an extruding machine having a casing which is provided with an outlet opening, said machine also having a movable extruding member adapted to be electrically driven, a switch for connectio-n in the circuit of said electrical drive to control it, said switch being provided with an operating member movably mounted on the machine adjacent to the force-feed mechanism, means for preventing a rotation of the plunger with respect to the gun, and means brought into engagement by operatorcontrolled partial rotation of the gun with respect to the extruding machine for connecting the plunger temporarily 'to the switch-operating member and for connecting the gun to the extruding machine to receive material extruded through said outlet opening.

HANS C. PAULSEN.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,178,908 Fisher Apr. 11, 1916 1,399,240 Bagley et a1 Dec. 6, 1921 2,229,476 Reichle Jan. 21, 1941 2,360,984 Schmitz Oct. 24, 1944 2,432,734 Doesken Dec. 16, 1947 2,441,222 Fuller May 11, 1948 FOREIGN PATENTS Number Country Date 492,462 Great Britain Sept. 21, 1938 

